Electric indicator and signal.



D. G. DAVIES.

ELEGTRIG INDICATOR AND SIGNAL.

APPLICATION FILED NOV. 16, 1908.

Patented Sept. 21, 1909.

1 finoentoz I ma]:

chrome Ja /dd DAVID G. DAVIES, 0F COEUR DALENE, IDAHO.

ELECTRIC INDICATOR AND SIGNAL.

- Specification of Letters-Patent.

To all whom it may concern: Be it known that I, DAVID G. DAVIES, a citizen of the United State residing at Coeur dAlene,. in the count of Kootenai and State of Idaho, have invented a new and useful Electric Indicator and Signal, of which the following is a specification.

This invention has reference to improvements in electric indicators and signals and is designed more particularlyfor the indication of fluid level by a suitable visual indicator located at a distance from the reservoir or receptacle for the fluid and also for the sounding of an audible signal for one or both extremes of fluid level.

In accordance with the present invention there is located in or in operative relation to the reservoir for the liquid, the level of which is to be indicated at a distance, a suitable receptacle containing a fluid susceptible to the differences in pressure of the liquid within the reservoir as the pressure of the (inferences in level of the liquid in the reservoir 1s caused to close electric clrcults m such order as to cause the indication at .a

distant indicatin instrument of such character as to revea to an observer the fluid level from time to time in the reservoir.

The invention is designed more particularly for the indication of water level in a water reservoir and especially the indication at a pumping-station of the water level in a distant reservoir into which the water from the pumping station is delivered. Various indicating means have been devised from time to time for such a purpose but all such means depend upon the operation of more or less complicated mechanisms which are liable to get out of order and are also subject to other defects which mitigate against their usefulness.

In accordance with the present invention the physical. properties of mercury are util: ized both as to its high specific gravity and its mobility under normal temperatures and 3 even under low temperatures. Furthermore, advantage is taken of the electric: conductivi-ty of mercury. To this end there is pro-- vided in accordance with the present 'invention a receptacle for mercury at or below; the lowestlevel it is designed to indicate in 5 i the reservoir and this reservoir of mercury? is put in communication with a .stand pipe at least its interior of insulating material and at stated, intervals this stand pipe is pierced by electric conductors connected in' Patented Sept. 21, 1909. Application filed November 16, 190.8. Serial No. 462 846.

for mercury, which stand pipe is made of or also operated by the changing level of the mercury column, v

The invention will be best understood from a consideration of the followingdescription taken in connection with the ac- .companying drawings forming a part of this specification, in which draw1ngs Figure 1 is a partly structural diagram.

illustrating the invention, and Fig. 2 is a view showing theapplication of, the invention to a water main.

Referring to the drawing .there is shown a reservoir 1 which may be a tank of suitable proportions or a masonry reservoir of as large proportions as desired, the showing.

in the drawing being typical only. Within the reservoir on the bottom thereof or at a 'point as low as or lower than the, lowest water level it is desired to indicate there is located a vessel or rece tacle 2, which in the particular instance un er consideration may be considered as an open iron vessel, although other materials unaffected by mercury andwhich either are or may be so protected as to be unafiected by. water. This vessel 2 is inicommunication at its lower part with a pipe .or conduit 3, which may also be of iron because ofits resistance .to the action of mercury, and also-because it is electro-conducting... Qutside the reservoir the pipe 3 is. directed upwardly and by means of a suitable coupling 4 is joined to an upright pipe .5 which .in the particular structure under consideration may be made of hard vulcanized rubber because of its resistance to the. action. of mercury and also because of its electric insulating properties. This however does not preclude the use of other materials of like properties or the use of metal pipe. with an insulating lining, the principal condition being that the pipe should have inner walls at least resistant to the action of mercury and also of insulating properties.

At' suitable distances apart the walls'oi the pipe are pierced by studs 6 of conducting.

material, which studs, if the pipe 5 be of insulating material neednot. be otherwise insulated. Since the specific gravity Ofmercury-is 13.6 the between the studs 6 will be to the differences in water level to be indicated as l to 13.6. Ifthefl water level chosen or if it be desired to indicate diffenent degrees of water level at different heights as when the steps between the indicated levels be varied unequally or progressively instead of evenly as in the case under consideration; v

At the distant point of indication say at the pumping station or at any other desired point there is located an indicator 9 which may be calibrated to respond to electric currents of strengths corresponding to the differences in water leveli-t is desired toindicats. on one side the indicator 9 is con-j nectedby an electric conducter 10 to the final conductor 7 'of the series connected to the studs 6 and this conductor 10 may include" a battery 11 orother suitable source of electric energy. On the other side the indicator 9 is connected by a conductor 12 to the iron pipe 3, or the conductor 12 may be replaced by suitable ground connections be-.'

tween the indicator 9 and the ground on one hand and the pipe 3 and the ground on the other hand. For this reason the con ductor 12 may be designated as the return or ground conductor whether the circuit be an all metal circuit or a grounded circuit in the ordinary use ofthe term. The conductor 12 or the grounded circuit replacing the same may include-an adjustable resistance 13 so as to balance the circuit for variations in the battery or other electric source 11' and to adjust the indicator 9 to difierent lengths of circuits between the reservoir and the indicator without the necessity of calibrating each indicator 9 for each separateinstallation. 3

'Assume that the reservoir 1 is empty and that wateris being pumped thereinto. As

the waterrises above the surface of the mercury 14 within the vessel 2 the column 'of mercury within the pipe 5 will begin to rise proportionately the increased pressure of the water on the mercury in the vessel 2 due to'the rise of water level. Ultimately the mercury column within the tube. 5 reaches the lowermost stud 6 and there is now estab lished a circuit from the current source 11 through the conductor 10 and through all the resistances 8120 the conductor .7 leading to the lowermost stud 6, thence by the mercury columnto the pipe 3 and by the conductor 12 or ground and through the adjustable resistance 13 to the indicator 9 and back to the current source 11. This current will cause a movement of the indicating hand of the indicator 9 over the dial of the indicator to an extent agreeable to the lowermost indicated water level. As the water in the reservoir. continues to rise the second stud 6 is coupled up inthe circuit by the rising mercury column and the resistance. between the second-conductor 7 and the lowermost conductor"? is bridged or short circuited so that a greater'current will now flow to'the indicator and the hand will be moved a commensurate distance. ter level, the column of mercury will follow and one'after anotherof the studs 6 will be reached and the resistances 8 will be bridged or short circuited until finally they are all cut outwhen the highest water level to be indicated has been reached, the hand on the indicator moving progressively forward as the water level ,has'risen. There is thus S0 with the rising wai produced an' indication of the water level due-to the increasing water pressure as the depth of the water is increased. When the water level falls then the reverse operation takes place and .the resistances 8' are progressively cut into vthe circuit so as to be active therein and thebattery current is cor- 'respondingly cut down and the indicator hand returns toward its initial position thus indicating the water level within the limit" determined upon-and by. the. predetermined steps whether the water be rismg or falling.

V The indicator-i9 will give visual indication or the water level at any time desired,

but it is advisable that an audiblesignal be given when the water level has reached a predetermined or has attained a predetermined maximum and the operator at the pumping station will thereby be noti-' .fied to either start the pumping to replenish the water supply or to stop the pump to prevent an overow of the reservoir. For this purpose there is provided in the pipe 5 another s'tud 15 and this stud is connected by conductor 16 to a batteryor other current source'17 which latter is through a conductor 18 connected to electro magnets 19 and these latter are coupled by a conductor 20. to the; pipe 4 either directly, or through the common conductor 12. The stud 15 is located between the lowermost stud 6 and the next stud or plug 6 so 55 means and a snap switch 35 whichmayl provided with the usual ofi and on---in" new that" on the rising Jmercury column w1 passed the lowermost I desired level it then quickly reach the stud or plug thus.

estabhshing a circuit" from the .battery 17 a through the-conductor 16 and :plug l5thence to the. mercury column-and pipe. 3to-the conductor 12.and by -Way of the conductor 20throu h-t-hemagnets -.19 and-back to the battery 1 through 'theconductor 18. This .will causethe ener 'za'tion ofthemagnets 19 a'nd-withinthe eld of these magnets is an armature 21 which is attracted as soon as the magnet becomes energized This arma ture is a bridging'conductor or carries-such 'arma'ture21 falls or is move a bridging-conductorfortwo circuit terminals 22 spaced apart and insulated. from one' another and one of theseterm mals is con-, nected by a conductor 23 to. the common conductor 12 while the other terminalis connected by a conductor 24 to a relay magneto 25 and this conductor24 may include a tery 26V or other source of -electric energy, When the bridging conductor 21 rests u on the terminals 22 then the circuit charge by the battery-26, is closed and the relay magnet 25 is'energized but when thema ets 19 are energized the armature or bridging conductor 21 is moved away from the terminals 22 net is thus deenergiz'ed.

' So long as the water level is above the predetermined sufiiciently to bring the mercury column into contact with the plug or stud 15 the rela magnet 25 remains inactive, but shoul the water level fall toward the predetermined minimum until the plug or stud 15 is no longer reached by the mercury column then the magnet 19 is deenergized and thebridgin conductor or into contact with the terminals 22 and the 'circuit fed by the battery 26- is closed and the magnet 25 isthen energized. The magnet 25 controls 45 an armature lever 27 againstthe action of a retract' v spring 28 vwhich latter tends to hold the ever against an inert back stop 29. In the path of the lever 27 in its direction of movement under the influence ofthe magnet 25 is a circuit terminal 30 connectedby a conductor 31 to a battery or other current source 32 and leading from the battery 32'- .back to the lever 27 is another conductor 33 in which conductor is included a bell-34 or other audibleLele'ctrically operated signgl' cations. When the magnet-25 is energized and 5 thearmature lever 27 is 'pulled against the" action of the-spring 28 until ineng'a "'ment with the terminal 30 then there is esta lished" a circuit'from the battery 32 to the-terminal 30 and armature lever 29 by the conductor 33 throu h the switch 35, the latter being as "back ,to the battery- 32-. .Underthese conditions the bell will and continueto ring so long as the circuit is intact. In order to avoid a continuous 'ringling'f of the. bell 34 after .the "pumping machinery has been set into operation and also before the water level has been raised sufliciently to bring the mer- 'cury' column into contact withlthe stud or plug 15, the switch 35 may :beturned to the ofli position thus preventing a further ringing of the bell. As' soon as the water level has risen sufficiently to cut out the magnet 25 then the switch .35should be again returned to the on position-so that the device is in condition to again give a signal should the water'level once moredrop to the minimum point. v Y

. Because" of the infrequent service the batteries 26 and 32 may be of small size and if desired of. the-open circuit type such as the ordinarydry batteries of commerce. The

batteries 11 and 17 being in almost constant service may be of the'l'on' life closed circuit? type known as the gravity battery, or any other suitable source of currentfor the purpose may :be employed.

When the mercury column hasrisen until the uppermost stud or'plu 6 is reached because of the rise of water evel to the max-.

point then the mercury cohunn also reaches another plug or stud 36 oonnectedby a branch conductor 37 to-the conductor 24 before-referred to. Now there is established a' circuit from the battery 26 through the conductor 24 and branchconductor 37 to the stud or plug 36 thence-by themeroury column to the conductor 12 and back to the battery 26 through'the relay magnet 25. This will cause the' attraction'of the armature 27 and the closure of the local circuit including alarm and on the inspection of the indicator 9 it will be ascertained that this alarm is a high water alarm. 1

It Wlll be understood, of course, thatthe. mercury vessel or container may be exterior to the reservoir insteadiof inside the same or maybe connected to a conduit leading from .the reservoir or source of supply since the device operates bypressure, and in practice it is often times "necessary to tap a main. I

"In Fig. 2 the invention is shown as ap-' plied to a main, although the arrangement wouldibe 'the:'same were the inventionapleading from the reservoir. rather than'to ,install the mercury vessel the reservoir.

plieddirectly to a reservoir with the mercury viesselexterior thereto; v The 'main 'l is tapped by a pipe 38 leading into a closed mercury vesselor container 2 "throughthe top thereofand the pipe 3. leads from the bottom ofthe wssel 2 1n the form .shown in'Fig. 2. The'pressure within-the main or reservoir is J communicated. to. the 65 sume to be closed, thence to the bell 34;.and mercury in the vessel 2 and causes a com 105 the alarm 34 thus to the operator an mensurate rise in the column of mercury in the p'pe 5., the operation beingthe same as in the form shown i'nFig.

In" the operation of the invention the variations-in level of the mercurj in the vessel or container may be negligible and therefore the variations of the mercury column in the pipe 5 will be, for all practical purposes, in direct proportion to variations in the weight or pressure of a fluid per unitmrea at a predetermined point, due to variation in the height'ofits surface above such predetermined point. I

What is claimed is 1. The combination with a reservoir for liquids, of an open vessel for mercury there- 'in, an electric conducting pipe leading from the mercury vessel to the exterior of the reservoir, an upright pipe leading from the electrically conducting pipe exterior to the reservoir, and formed ofnon-conducting material, contacts carried by the non-conducting-pipe, a series of resistances connected to the contacts in order, a charged electric circuit connected at the ends to the conducting pipe and to one end of the series of resistances respectively, an indicator 1n said circuit responslve to current varlations, a2 local charged alarm circuit, a relay controlling the said local alarm circuit, a charged circuit including the relay, and connected at one end to a contact at the upper end of the ill-- sulating pipe, and at theother end electrically connected to the conducting pipe, an-' other-circuit bridged across the charged relay circuit, and another charged relay ciruit controlling the bridging circuit and con- I Qected to the conducting pipe and to a lower contact in the insulating pipe.

2. A means for indicating fluid levels, 40

' comprising. a single mercury column and a container therefor, said column bein responsive to difierences in weight of. di erent levels of a column of the fluid, a charged electric circuit, means under the control of v means contro ed by the first normally closed circuit. for holding the said last-named. sepa-- rately charged circuit normally open, an alarm circuit controlled by the normally open circuit, and means for closing the normally open circuit around the break therein by the mercury column when the latter reaches the maximum level. I

Intestimony thatI claim'the foregoing as my own, I have hereto aflixed my slgnature in the presence of two witnesses.

' DAVID G. DAVIES. Witnesses:

GEO. HAnnnve, T. C. Hnnm 

